A Long Term Evolution (LTE) system architecture mainly includes an access network and a core network. The access network mainly includes a base station, and the core network mainly includes a mobility management entity (MME), a serving gateway (S-GW), and a packet data network gateway (P-GW). Wireless communication between terminals can be implemented by using the LTE system architecture.
As shown in FIG. 1, when a user initiates communication with a target user, the user may use a first terminal to send a communication request to an IMS (Internet Protocol Multimedia Subsystem) by using a first base station, a first S-GW (an S-GW to which a first MME belongs), and a first P-GW (a P-GW to which the first S-GW belongs). The IMS parses the communication request and learns that a communication target is a second terminal. Then, the IMS sends a command instruction to a second PCRF (policy and charging rules function) (a PCRF to which a second P-GW belongs), and requires the PCRF to trigger bearer setup of a corresponding service, so as to establish a dedicated data transmission channel from the second P-GW (a P-GW that provides a service for the second terminal) to a second S-GW (an S-GW that provides a service for the second terminal), from the second S-GW to a second base station (a base station to which the second terminal is attached), and from the second base station to the second terminal. At the same time, the IMS further sends a command instruction to a first PCRF (a PCRF to which the first P-GW belongs), and requires the PCRF to trigger bearer setup of a corresponding service, so as to establish a dedicated data transmission channel from the first P-GW (a P-GW that provides a service for the first terminal) to the first S-GW (an S-GW that provides a service for the first terminal), from the first S-GW to the first base station (a base station to which the first terminal is attached), and from the first base station to the first terminal. The dedicated data transmission channel is used to transmit communication data exchanged between the first terminal and the second terminal.
In a process of implementing the present invention, the inventor finds that at least the following problems exist in the prior art.
Generally, when the two terminals communicate with each other by using the foregoing method, communication data can be transmitted to the second terminal only after passing through the first base station, the first S-GW, the first P-GW, the IMS, the second P-GW, and the second S-GW. Therefore, there is a relatively long communication delay between the terminals.